To add a user to a role, you must use the stored procedure sp_addrolemember.
First you must select the database that contains the user and the role.
USE YourDatabaseHere GO EXEC sp_addrolemember 'db_datareader', 'JohnJacobs' EXEC sp_addrolemember 'db_datawriter', 'JohnJacobs' EXEC sp_addrolemember 'db_accessadmin', 'JohnJacobs' EXEC sp_addrolemember 'db_backupoperator', 'JohnJacobs' EXEC sp_addrolemember 'db_ddladmin', 'JohnJacobs' EXEC sp_addrolemember 'db_denydatareader', 'JohnJacobs' EXEC sp_addrolemember 'db_denydatawriter', 'JohnJacobs' EXEC sp_addrolemember 'db_owner', 'JohnJacobs' EXEC sp_addrolemember 'db_securityadmin', 'JohnJacobs'
The example above shows all predefined roles in a database.

